Question: When was Eric Piolle the the Head of Government of Grenoble?
Paraphrase: What was the timeframe that Eric Piolle was the Head of the Government of Grenoble?
SPARQL (Wikidata): SELECT ?value WHERE { wd:Q1289 p:P6 ?s . ?s ps:P6 wd:Q16007948 . ?s pq:P580 ?value}